Abstract Library

#4588 Spatial transcriptomics identifies Wnt signalling in multifocal ileal neuroendocrine tumours

Introduction: Ileal neuroendocrine tumours (i-NETs) often present with multiple primary tumours (>30-40%). Recent studies showed no shared somatic mutations in multiple primary tumours, highlighting the need to examine the tumour microenvironment in tumorigenesis. The Wnt signalling pathway is crucial for organ stem cell regulation. While the Wnt/β-catenin pathway influences prostate and pancreatic NET/Cs, its role in i-NETs remains unclear.

Conference:

Presenting Author:

Authors: Yogo A, Akanuma N, Kim G, Thirlwell C, Mäkinen N,

Keywords: Wnt Signalling, Spatial Transcriptomics,

#4539 Single-nucleus profiling of the tumour microenvironment in SI-NET patients

Introduction: Small intestinal neuroendocrine tumours (SI-NETs) are frequently present as multiple synchronous primary tumours in the small bowel. They are thought to arise from enterochromaffin (EC) cells in the gut, which account for less than 1% of the intestinal epithelium. Previously reported lack of shared somatic driver alterations in SI-NETs suggests that other, non-genetic mechanisms are likely involved in their tumorigenesis.

Conference:

Presenting Author: Mäkinen N

Authors: Mäkinen N, Kasai Y, Kim G, Thirlwell C, Nakakura E,

Keywords: small intestinal NET, tumour microenvironment, single-nucleus sequencing,

#4256 Epigenetic prediction of aging and metabolic traits provides insight into tumor biology in multi-focal ileal neuroendocrine tumors

Introduction: Approximately half of small intestinal neuroendocrine tumors (siNETs) are multifocal, and recent investigations into the genetic architecture of these tumors have found that they are not clonal. Due to the low mutational rate and slow growing nature of these small tumors, the ‘timing’ of the development of individual tumors has not been possible.

Conference:

Presenting Author:

Authors: Webster A, Makinen N, Ecker S, Beck S, Nakakura E,

Keywords: DNA methylation, Epigenetics, Multifocal Ileal Neuroendocrine Tumor, Multifocal Small Instestinal NET, Metabolic Traits,

#4166 Characterising the tumor microenvironment of multifocal small intestinal NETs

Introduction: Small intestinal neuroendocrine tumors (SI-NETs) are thought to arise from enterochromaffin cells of the gut, often with multiple synchronous primary tumors. Recently, we showed that synchronous primary tumors from the same SI-NET patient display distinct somatic mutational profiles, suggesting that these tumors originate independently, despite few clear driver mutations. Thus, new mechanistic insights into multifocal SI-NETs are urgently needed.

Conference:

Presenting Author:

Authors: Mäkinen N, Lee I, Dohlman A, Gao T, Zhang Z,

Keywords: small intestinal NET, tumor microenvironment, tumor microbiome,

#3805 Transcriptomic analyses of multifocal ileal neuroendocrine tumors

Introduction: Small intestinal neuroendocrine tumors are mostly located in the distal ileum with a high incidence of multiple synchronous primary tumors. To date, loss of heterozygosity (LOH) at chr18 has been the most frequent genomic event identified, occurring in ~60% of tumors. Recently, we showed that synchronous primary tumors from the same ileal NET patient display distinct somatic mutational profiles, including distinct patterns of chr18 LOH, suggesting these tumors originate independently. Thus, new mechanistic insights into multifocal ileal NETs are urgently needed.

Conference:

Presenting Author:

Authors: Mäkinen N, Zhang Z, Munn S, Kasai Y, Kim G,

Keywords: Multifocal ileal NETs, RNA-sequencing, Gene expression,